Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
With the gradual transition to digital television (DTV) as well as development of efficient audio and video compression techniques, considerable amount of unused channels have been generated in the TV spectrum (VHF and UHF bands) collectively known as TV White Spaces (TVWS). TV white spaces are location and time dependent (based on active TV broadcast stations in an area and when those stations broadcast).
On the other hand, wireless technologies are proliferating in all aspects of personal, commercial, and other use. From home computer networks (e.g., Wireless Local Area Networks “WLANs”) to wireless sensor networks, Wireless Regional Area Networks (WRANs), an increasingly large number of devices and systems utilize and have a need for wireless spectrum. Because the radio frequency (RF) spectrum is inherently limited, attempts to increase efficiency of wireless communications include various sharing schemes for existing dedicated portions of the RF spectrum. For example, standardization activities targeting TVWS include IEEE 802.22 for WRANs, IEEE 802.11af for personal/portable devices resulting in ad hoc networks, and IEEE 802.19.1 Task Groups (TGs) work on supporting coexistence in TVWS.
The present disclosure appreciates that there are several limitations with existing spectrum sharing technologies, specifically directed to TVWS. For example, it is a challenging task to detect these white spaces, which are in-deterministic over time and space, for possible usage by opportunistic secondary user networks.